Science & technology | Maybe she’s barn with it

A new study asks whether racehorses have hit their genetic peak

But the breeders trying to improve them may be missing a trick

Eadweard Muybridge. Horses. Gallop; thoroughbred bay mare (Annie G) with male rider, 1872-1875 — They were slower back thenImage: Getty Images

Jun 7th 2023

For decades there was an apparent paradox in horse-racing. The sport is lucrative (Mage, the winner of this year’s Kentucky Derby, earned his owner $1.9m) and simple—the fastest horse wins. Horses with good results and a good pedigree are used as breeding stock for the next generation. Horse-breeders were armed with plenty of data, a single trait to optimise, and strong incentives to do so. Yet several studies suggested that, despite their efforts, race times were not improving.

This article appeared in the Science & technology section of the print edition under the headline “Maybe she’s barn with it”